Sliding fabric

ABSTRACT

A sliding fabric exhibits a small amount of compression in the thickness direction under load application, does not cause generation of play between members, and is superior in sliding properties and durability. The sliding fabric is configured such that fluororesin fibers (X) and other fibers (Y) are alternately arranged as warps and/or wefts on at least one side of the fabric and the amount of compression of the fabric is 25 μm or less.

TECHNICAL FIELD

This disclosure relates to a sliding fabric containing a fluororesinfiber suitable as a sliding material.

BACKGROUND

Conventionally, fluororesin has been used with it being laminated orcoated on a surface layer of a sliding member by taking advantage of itslow friction coefficient. When fluororesin is laminated or coated,however, a fluororesin film is thin and readily peels off due to itsnon-adhesion property and therefore it has been necessary to repeatlamination or coating to maintain sliding properties for a long term. Tosolve such a drawback, a sliding member has been developed, includingfluororesin in the form of fibers arranged as a woven or knitted fabricor a non-woven fabric on the surface of the sliding member to improveits friction durability, which is then made a composite member with awoven or knitted fabric having an easily-adhering nature with othermaterials for firmer adhesion.

For example, JP-A-2005-220486 discloses a woven fabric in which fluorinefiber yarns and high-strength fiber yarns having a tensile strength of 2GPa or more are interwoven, where the woven fabric is a fluorine fiberinterwoven fabric characterized in that fluorine fibers cover 30% ormore of the surface area of any one side of the woven fabric. Thanks tosuch a configuration, it is possible to provide a composite materialsliding material superior in durability and mechanical characteristicsthat exert a low friction property of the fluorine fibers and thefluorine fibers do not peel off when it is used as a base material of acomposite material bearing.

Further, JP-A-2015-124450 discloses a multilayered woven fabric composedof a sliding woven fabric containing PTFE fibers and a base wovenfabric, where the multilayered woven fabric is a heat wear-resistantfabric having been made high in heat resistance and wear resistance andcapable of exerting a long-term sliding property even under a highertemperature environment than before by optimally configuring the basesurface.

However, since the fluorine fiber interwoven fabric disclosed inJP-A-2005-220486 is a woven fabric in which fluorine fiber yarns andhigh-strength fiber yarns having a tensile strength of 2 GPa or more areinterwoven, it is problematic in that depending on the high-strengthfiber to be used, the tensile elastic modulus is high and easily damagesa mating material and the sliding property as a woven fabric isdeteriorated and, as a result, long-term durability cannot be expected.In addition, when used for applications such as bearing members, playmay occur between the members if the amount of compression in thethickness direction of the fluorine fiber interwoven fabric under loadapplication is large.

In JP-A-2015-124450, when the amount of compression in the thicknessdirection is large under load application, play tends to occur betweenmembers and, therefore, there is still room for improvement to make thesliding property to be exhibited for a longer period of time.

It could therefore be helpful to provide a sliding fabric that exhibitsa small amount of compression in the thickness direction under loadapplication, does not cause generation of play between members, and issuperior in sliding properties and durability.

SUMMARY

We thus provide:

(1) A sliding fabric in which fluororesin fibers (X) and other fibers(Y) are alternately arranged as warps and/or wefts on at least one sideof the fabric and the amount of compression of the fabric is 25 μm orless.

(2) The sliding fabric according to the above (1), wherein an intervalbetween fluororesin fibers (X) positioned on both sides of the otherfiber (Y) is in the range of 20 to 3500 μm.

(3) The sliding fabric according to the above (1), wherein the otherfibers (Y) are of a single type.

(4) The sliding fabric according to the above (3), wherein an equalnumber of the fluororesin fibers (X) and the other fibers (Y) arealternately arranged.

(5) The sliding fabric according to the above (3) or (4), wherein 1 to 4fibers of the fluororesin fibers (X) and 1 to 4 fibers of the otherfibers (Y) are alternately arranged.

(6) The sliding fabric according to the above (1), wherein the finenessof the other fibers (Y) is in a range of 50 to 800 dtex.

(7) The sliding fabric according to the above (1), wherein the tensileelastic modulus of the other fibers (Y) is in a range of 20 to 800cN/dtex.

(8) The sliding fabric according to the above (1), wherein theelongation of the other fibers (Y) is 3% or more.

(9) The sliding fabric according to any one of the above (1) to (8),wherein the sliding fabric is a woven fabric.

(10) The sliding fabric according to the above (9), wherein the slidingfabric is a woven fabric composed of one layer or two layers.

(11) The sliding fabric according to the above (9) or (10), wherein thesliding fabric is a plain-woven fabric.

(12) The sliding fabric according to any one of the above (1) to (11),wherein the sliding fabric has a thickness of 1 mm or less.

By alternately arranging fluororesin fibers and other fibers as warpsand/or wefts on at least one side of fabric and by adjusting the amountof compression of the fabric to 25 μm or less, we provide a slidingfabric that exhibits a small amount of compression in the thicknessdirection under load application and does not cause generation of playbetween members even when used as a sliding material for suchapplications as a bearing member, and is superior in sliding propertiesand durability.

DETAILED DESCRIPTION

The sliding fabric is characterized in that fluororesin fibers (X) andother fibers (Y) are alternately arranged as yarns constituting warps orwefts or both warps and wefts on at least one side of the fabric and theamount of compression of the fabric Is 25 μm or less.

Fluororesin Fiber (X)

The fluororesin that is a component of the fluororesin fiber (X) may beany resin composed of monomer units containing one or more fluorineatoms in the main chain or a side chain thereof. Above all, thosecomposed of monomer units having a larger number of fluorine atoms arepreferred.

The monomer units containing one or more fluorine atoms are preferablycontained in an amount of 70 mol % or more, more preferably 90 mol % ormore, and further preferably contains 95 mol % or more of the repeatingstructural units of the polymer.

Examples of the monomer containing one or more fluorine atoms includefluorine atom-containing vinyl monomers, such as tetrafluoroethylene,hexafluoropropylene, and chlorotrifluoroethylene, among whichtetrafluoroethylene is preferably used.

As the fluororesin, polytetrafluoroethylene (PTFE),tetrafluoroethylene-hexafluoropropylene copolymer (FEP),tetrafluoroethylene-p-fluoroalkyl vinyl ether copolymer (PFA),polychlorotrifluoroethylene (PCTFE), ethylene-tetrafluoroethylenecopolymer (ETFE) and the like, may be used singly or in combination oftwo or more species thereof.

In a fluororesin containing tetrafluoroethylene units, thetetrafluoroethylene unit content is preferably higher in view of slidingcharacteristics, and PTFE fibers as a homopolymer are most preferablyused.

As the form of the fluororesin fiber (X), any of a monofilament composedof one filament and a multifilament composed of a plurality of filamentscan be used.

The total fineness of the fibers composed of a monofilament or amultifilament constituting the fluororesin fiber (X) is preferably 50 to2000 dtex, more preferably 100 to 1000 dtex. When the total fineness ofthe fibers constituting the fabric is 50 dtex or more, the strength ofthe fibers is large, and so breakage of yarns during weaving can bereduced and so the process passing property can be improved. When thetotal fineness is 2000 dtex or less, the fabric is small in thicknessand the amount of compression in the thickness direction can be reducedunder load application so that play between members can be suppressedand long-term durability is improved.

Other Fiber (Y)

As other fibers (Y), fibers of polyphenylene sulfide (PPS),polyparaphenylene terephthalamide, polymetaphenylene isophthalamide,glass, carbon, nylon, polyester, high molecular weight polyethylene(molecular weight: 1,000,000 to 7,000,000) can be used. These may beused singly or in combination of two or more thereof. Among them, PPSfibers that are low in tensile elastic modulus and superior in hightemperature resistance characteristics in continuous use, are preferablyused. It is preferable to use polyparaphenylene terephthalamide, glassfibers and the like, that have good high strength properties under ahigh-load use environment. When the non-sliding surface is required tohave adhesion performance, it is preferable to use nylon fibers.

As the form of the other fiber (Y), any of a monofilament composed ofone filament and a multifilament composed of a plurality of filamentscan be used.

The total fineness of the fibers composed of a monofilament or amultifilament constituting the other fiber (Y) is preferably 50 to 800dtex, more preferably 100 to 300 dtex. When the total fineness of thefibers constituting the fabric is 50 dtex or more, the strength of thefibers is large, and so breakage of yarns during weaving can be reducedand so the process passing property can be improved. When the totalfineness is 800 dtex or less, the fabric is small in thickness and theamount of compression in the thickness direction can be reduced underload application so that generation of play between members can besuppressed and long-term durability is improved.

The tensile elastic modulus of the fibers composed of a monofilament ora multifilament constituting the other fiber (Y) is preferably 20 to 800cN/dtex, more preferably 20 to 100 cN/dtex. When the tensile elasticmodulus of the fibers constituting the fabric is 20 cN/dtex or more, thestrength of the fiber is high and resistance to shearing force due towear of the fabric can be strengthened so that the fabric is difficultto break even when worn. When the tensile elastic modulus is 800 cN/dtexor less, the rigidity of the fibers is not excessively high and thefibers are difficult to damage mating materials so increase in thefriction coefficient of a friction interface can be suppressed andlong-term durability is improved.

When fibers generally having a high tensile elastic modulus such as highmolecular weight PE and carbon fiber, are used, the compression ratio isadjusted not to exceed our range by reducing the fineness, reducing theuse amount or the like as necessary.

Elongation of the fibers composed of a monofilament or a multifilamentconstituting the other fiber (Y) is preferably 3% or more, morepreferably 10 to 50%. When the elongation of the fibers constituting thefabric is 3% or more, stretching performance of the fibers is large, andso breakage of yarns during weaving can be reduced and so the processpassing property can be improved. When the elongation is 10 to 50%,since this is at the same level as the elongation of the fluororesinfibers, it is easy to set conditions for weaving, wrinkles caused byshrinkage difference are less likely to occur on a fabric surface duringpost processing so that the process passing property is improved.

Sliding Fabric

In the sliding fabric, fluororesin fibers (X) and other fibers (Y) arealternately arranged as yarns constituting warps and/or wefts on atleast one side of the fabric.

Examples of the mode in which the fluororesin fibers (X) and otherfibers (Y) are alternately arranged on at least one side of the fabricinclude:

A: 1 fiber/B: 1 fiber/C: 1 fiber;A: 3 fibers/B: 3 fibers/C: 3 fibers; andA: 1 fiber/B: 3 fibers/C: 2 fibers/A: 3 fibers/B: 4 fibers/C: 1 fiber,where a fluororesin fiber (X) is represented by A, other fiber (Y) isrepresented by B and C.

In one example, fluororesin fibers (X) and other fibers (Y) arealternately arranged as warps, and either fluororesin fibers (X) orother fibers (Y) are arranged as wefts. In another example, eitherfluorocarbon resin fibers (X) or other fibers (Y) are arranged as warps,and fluororesin fibers (X) and other fibers (Y) are alternately arrangedas wefts. In another example, both warps and wefts are fluororesinfibers (X) and other fibers (Y) alternately arranged. Above all, in apreferred configuration, both warps and wefts are fluororesin fibers (X)and other fibers (Y) alternately arranged. As a result, fluororesinfibers (X) and other fibers (Y) can be arranged alternately in both thelongitudinal direction and the transverse direction of the fabric, andso a low friction property retained by the fluororesin fibers (X) and anaggregate effect functioning as fabric strength retained by the otherfibers (Y) can be sufficiently exhibited regardless of thedirectionality of the fabric.

“Fluororesin fibers (X) and other fibers (Y) are alternately arranged”means that the fluorine fibers (X) and one type or two or more types ofother fibers (Y) are arranged by turns. This is a situation where thefluororesin fibers (X) and the other fibers (Y) are mixed in onedirection of the fabric.

In the sliding fabric, an interval between the fluororesin fibers (X)positioned on both sides of the other fiber (Y) is preferably 20 to 3500μm, more preferably 50 to 1000 μm. When the interval is 20 μm or more,the other fibers are not excessively thin and strength can be secured sothat an aggregate effect to retain fabric strength can be exhibited andthe durability of the fabric is improved. When the interval is 3500 μmor less, the distance between the fluororesin fibers is not excessivelylarge and a fluorine film is easily formed at the friction interface sothat the sliding properties and the durability of the fabric areimproved.

The interval of the fluorine fibers (X) referred to herein shall beevaluated, for example, between A1-A2 when two types (A1 and A2) as thefluorine fibers (X) and four types (B1, B2, B3 and B4) as the otherfibers (Y) are used and there is an arrangement in whichA1/B1/B2/A2/B3/B4 is repeated.

As to the other fibers (Y), one type or two or more types thereof can beused, but they are preferable be of one type. “One type” as referred toherein shall mean that the materials constituting the fibers are thesame. The same type (one type) of polymers refers to polymers containingcommon main repeating units such as nylon 66's and polyethyleneterephthalates and, for example, a combination of a homopolymer and acopolymer is also acceptable as the same type of polymers.

When fibers different from each other (two or more types) are used asthe other fibers (Y), they differ in stretching/shrinking performance.Therefore, a smaller number of types of fibers used leads to a situationwhere it is easy to set conditions for weaving, wrinkles caused byshrinkage difference are less likely to occur on a fabric surface duringpost processing so that the process passing property is improved.

Further, in the sliding fabric, it is preferable that an equal number ofthe fluororesin fibers (X) and one type of other fibers (Y) arealternately arranged.

Examples of the mode in which an equal number of fluororesin fibers (X)and one type of other fibers (Y) are alternately arranged include:

A: 1 fiber/B: 1 fiber;A: 5 fibers/B: 5 fibers; andA: 10 fibers/B: 10 fibers,where a fluororesin fiber (X) is represented by A and the other fiber(Y) is represented by B.

As a result, fluororesin fibers (X) and other fibers (Y) are arranged atthe same proportion and evenly so that a low friction property retainedby the fluororesin fibers (X) and an aggregated effect functioning asfabric strength retained by the other fibers (Y) can be sufficientlyexhibited.

It is further preferable that 1 to 4 fluororesin fibers (X) and 1 to 4fibers of one type of other fibers (Y) are alternately arranged.

Examples of the mode in which 1 to 4 fibers of fluororesin fibers (X)and 1 to 4 fibers of one type of other fibers (Y) are alternatelyarranged include:

A: 1 fiber/B: 1 fiber;A: 2 fibers/B: 2 fibers;A: 3 fibers/B: 3 fibers; andA: 4 fibers/B: 4 fibers,where a fluororesin fiber (X) is represented by A and the other fiber(Y) is represented by B.

Due to this, it is easy to form a film from the fluororesin on a slidingsurface through reduction of the interval between the fluororesin fibers(X) and it is possible to reduce friction as a sliding fabric.

The amount of compression of the sliding fabric is 25 μm or less. Theamount of compression is preferably 10 μm or less. By adopting the aboveconfiguration, it is possible to obtain a sliding fabric which exhibitsa small amount of compression in the thickness direction under loadapplication, does not cause generation of play between members, and issuperior in sliding properties and durability. When the amount ofcompression of the sliding fabric exceeds 25 μm, the amount ofcompression in the thickness direction under load application becomeslarge and play may occur between members so that good long-termdurability cannot be expected. It is preferable that the amount ofcompression of the sliding fabric is 10 μm or less because, if so, theamount of compression in the thickness direction is small even under aheavy load, no play occurs between members, and long-term durability isimproved.

The amount of compression of the sliding fabric is calculated by thefollowing calculation formula.

Amount of compression=T ₀ −T ₁

Wherein T₀: the thickness attained when an initial load of 50 cN/cm² wasapplied T₁: the thickness attained when a constant load of 300 cN/cm²was applied for 1 minute.

To suppress the amount of compression within the above range, it ispreferable to use a yarn with a low fineness or a single layer fabric.In addition, post-processing methods such as calendering, pressing andthe like are also preferable.

As the form of the sliding fabric, any of a woven fabric, a knittedfabric, and a multilayered composite material obtained by multilayingthese fabrics can be applied, but a woven fabric is preferred because itis better that denseness, smoothness and the like are higher. As thewoven fabric may be either of a single layer or a multilayer wovenfabric including two or more layers, but a woven fabric composed of onelayer or two layers is preferable because it is preferable that theamount of compression is lower.

As the configuration of the sliding fabric, plain-woven fabric, twilledfabric, satin and other tissues can be applied, but plain-woven fabricis preferable because it is better that denseness, strength and the likeare higher.

The thickness of the sliding fabric is preferably 1 mm or less, morepreferably 0.3 mm or less. When the thickness of the sliding fabric is 1mm or less, it is possible to obtain a sliding fabric which exhibits asmall amount of compression in the thickness direction under loadapplication, does not cause generation of play between members, and issuperior in sliding properties and durability.

To further improve durability, it is also possible to use the slidingfabric with it being impregnated with resin. As the resin with which thesliding fabric is impregnated, thermosetting resin or thermoplasticresin may be used. Examples of the thermosetting resin include, but arenot limited to, phenol resin, melamine resin, urea resin, unsaturatedpolyester resin, epoxy resin, polyurethane resin, diallyl phthalateresin, silicon resin, polyimide resin, vinyl ester resin and theirmodified resins, and examples of the thermoplastic resin include, butnot limited to, vinyl chloride resin, polystyrene, ABS resin,polyethylene, polypropylene, fluororesin, polyamide resin, polyacetalresin, polycarbonate resin, polyester and polyamide as well as syntheticrubber or elastomer such as thermoplastic polyurethane, butadienerubber, nitrile rubber, neoprene and polyester, which can be usedpreferably. Among them, resin mainly containing phenol resin andpolyvinylbutyral resin, unsaturated polyester resin, vinyl ester resin,polyolefin-based resins such as polyethylene or polypropylene, andpolyester resin are preferably used in terms of impact resistance,dimension stability, strength, cost and the like. Such thermosettingresin or thermoplastic resin may contain various additives usually usedfor the industrial purpose or use to improve productivity at themanufacturing steps or the processing steps or to improve theircharacteristics. For example, they may contain additives, such asmodifier, plasticizer, filler, mold-releasing agent, colorant, anddiluent. Mainly contained in this example refers to a component of thelargest ratio by weight among the components other than solvent, and ina resin mainly containing phenol resin and polyvinylbutyral resin, thismeans that the ratios by weight of these two types of resin are thelargest and the second largest (random order).

For a generally used method of impregnating the sliding fabric withresin, when thermosetting resin is used, the thermosetting resin may bedissolved in solvent to prepare for varnish, which may then be coated onthe fabric for impregnation by knife coating processing, roll coatingprocessing, comma coat processing, gravure coating processing or thelike. When thermoplastic resin is used, melting extrusion lamination orthe like is commonly used.

A fluorine-based lubricant may be added as needed to the sliding fabric.

The sliding fabric obtained in such a way has a structure where theother fibers (Y) firmly restrains the fluororesin fibers (X) asaggregates to maintain the fabric strength and abraded fluororesinfibers (X) are accumulated by the other fibers (Y) so that it canexhibit a sliding property for a long period of time, and there can beprovided a sliding fabric which exhibits a small amount of compressionin the thickness direction under load application due to its smallamount of compression, does not cause generation of play betweenmembers, and is superior in durability.

EXAMPLES

Hereafter, examples will be described together with comparativeexamples.

Methods of measuring characteristics used in the examples are asfollows.

(1) Amount of Compression of Fabric

According to JIS L 1096: 2010 (Testing methods for woven and knittedfabrics), a fabric was sampled into a size of 5 cm×5 cm.

Using a SE-15 type compression amount testing instrument as acompression amount analyzer, the sample prepared was placed slowly on a2 cm² probe, and a measuring handle was turned slowly in the DOWNdirection to apply a load; a thickness T₀ attained when a load of 100 cNwas applied was read and, a thickness T₁ when a load of 600 cN wasapplied for 1 minute was read, and then, an amount of compression wascalculated from the following formula.

Amount of compression=T ₀ −T ₁

(2) Interval Between Fluororesin Fibers (X) Located on Both Sides ofOther Fiber (Y) in the Sliding Fabric

Based on a photograph taken by enlarging the surface of the woven fabricon which fluororesin fibers (X) and the other fibers (Y) are alternatelyarranged by 30 times with a microscope VHX-2000 manufactured by Keyence,the minimum interval between the fluororesin fibers (X) located on bothsides of the other fiber (Y) was measured at n=5, and the average valuewas calculated. As to the interval, a distance between an end of one offluororesin fibers where the end is located on a side adjacent to another fiber (Y) and an end of another fluororesin fiber where the end islocated on a side adjacent to the other fiber (Y), where the ends of thefluororesin fibers are arranged across the other fiber (Y), wasmeasured.

(3) Fineness of Fiber

The fineness of fibers was measured according to JIS L 1013: 2010(Testing methods for man-made filament yarns).

(4) Tensile Elastic Modulus of Fiber

The tensile elastic modulus of fibers was measured in accordance withMethod B disclosed in Section 8.9 of JIS L 1013: 2010 (Testing methodsfor man-made filament yarns).

(5) Elongation of Fiber

The elongation of fibers was measured according to JIS L 1013: 2010(Testing methods for man-made filament yarns).

(6) Thickness of Fabric

The thickness of fabrics was measured according to JIS L 1013: 2010(Testing methods for woven and knitted fabrics).

(7) Ring Wear Test (Friction Wear Test)

According to Method A of JIS K 7218: 1986 (Testing Methods for SlidingWear Resistance of Plastics), a fabric was sampled in a length of 30 mmand a width of 30 mm, and was placed on a POM resin plate with the samedimensions and a thickness of 2 mm and then is fixed to a sample holder.

The mating material used is made of S45C, and has a hollow cylindricalshape of 25.6 mm in outer diameter, 20 mm in inner diameter and 15 mm inlength. The surface is polished with sandpaper so that the roughness is0.8 μm±0.1 Ra, which is measured by a roughness tester (manufactured byMitsutoyo Corporation, SJ-201).

As the ring wear tester, MODEL: EFM-III-EN manufactured by Orientec wasused, and a test was performed at a friction load of 1 MPa and africtional speed of 180 mm/second to measure the sliding torque untilthe frictional sliding distance of 6000 m. Then the friction coefficientat a stable part was calculated, and the surface state of the fabricsample after sliding was observed. A sample having substantially nowearing was rated as ⊙, a sample having wearing but having a stablefriction coefficient was rated as ◯, a sample having wearing and anincreased friction coefficient was rated as A, and a sample where thefabric was broken was rated as x.

(8) Play

The obtained fabric was used as a sliding material of a bearing and thedegree of play between the members was checked for a period of 3 months,and when there was almost no play was marked as ⊙, when there was aslight play was marked as ◯, when there was a remarkable play but nobreakage was marked as Δ, and when the fabric was broken was marked asx.

Example 1

A single plain woven fabric was produced with a loom to attain a weavingdensity of 70 warps+70 wefts/inch (2.54 cm) using PPS fibers having 220dtex, a tensile elastic modulus of 40 cN/dtex and an elongation of 30%and PTFE fibers having 440 dtex as warps and wefts while alternatelyarranging them at 1 (fiber): 1 (fiber). Then refining was performedthereto in a refining tank at 80° C., and the fabric was set at 200° C.

The amount of compression of this woven fabric, the interval of thefluororesin fibers located on both sides of the other fiber, thethickness, the result evaluated with a friction wear testing machine,and the result of the evaluation of play as a bearing sliding materialare summarized in Table 1.

Example 2

As a sliding layer, glass fibers having 300 dtex, a tensile elasticmodulus of 300 cN/dtex and an elongation of 3.5%, nylon fibers having100 dtex, a tensile elastic modulus of 40 cN/dtex and an elongation of40%, and PTFE fibers having 220 dtex were alternately arranged at 1(fiber): 3 (fibers): 3 (fibers) and used as warps, and nylon fibershaving 100 dtex, a tensile elastic modulus of 40 cN/dtex and anelongation of 40% were used as wefts. In addition, as a base layer,nylon fibers having 100 dtex, a tensile elastic modulus of 40 cN/dtexand an elongation of 40% were used as warps and wefts. Then, atwo-layered woven fabric in which the sliding layer was twilled fabricand the base layer was plain woven fabric was produced with a loom so asto have a weaving density of the sliding layer of 85 warps+100wefts/inch (2.54 cm) and a weaving density of 100 warps+100 wefts/inch(2.54 cm). Then refining was performed thereto in a refining tank at 80°C., and the fabric was set at 200° C. Thereafter, impregnation with afluororesin was performed by a roll coating processing system.

The amount of compression of this woven fabric, the interval of thefluororesin fibers located on both sides of the other fiber, thethickness, the result evaluated with a friction wear testing machine,and the result of the evaluation of play as a bearing sliding materialare summarized in Table 1.

Example 3

A two-layered knitted fabric was produced with a warp knitting machineto attain a number of courses of 29 courses/inch (2.54 cm) and a numberof wales of 19 wales/inch (2.54 cm) using nylon fibers having 220 dtex,a tensile elastic modulus of 40 cN/dtex and an elongation of 40% andPTFE fibers having 440 dtex as front warps while alternately arrangingthem at 1 (fiber): 1 (fiber): 3 (fibers): 2 (fibers): 1 (fiber): 4(fibers), and also using PET fibers having 560 dtex, a tensile elasticmodulus of 120 cN/dtex and an elongation of 40% as rear warps. Thenrefining was performed thereto in a refining tank at 80° C., and thefabric was set at 200° C.

The amount of compression of this knitted fabric, the interval of thefluororesin fibers located on both sides of the other fiber, thethickness, the result evaluated with a friction wear testing machine,and the result of the evaluation of play as a bearing sliding materialare summarized in Table 1.

Example 4

A single plain woven fabric was produced with a loom to attain a weavingdensity of 25 warps+25 wefts/inch (2.54 cm) using carbon fibers having40 dtex, a tensile elastic modulus of 1300 cN/dtex and an elongation of1% and PTFE fibers having 220 dtex as warps and wefts while alternatelyarranging them at 4 (fibers): 4 (fibers). Then refining was performedthereto in a refining tank at 80° C., and the fabric was set at 200° C.In addition, the fabric was impregnated with fluororesin to prepare aprepreg and a composite material was formed.

The amount of compression of this composite material, the interval ofthe fluororesin fibers located on both sides of the other fiber, thethickness, the result evaluated with a friction wear testing machine,and the result of the evaluation of play as a bearing sliding materialare summarized in Table 1.

Comparative Example 1

A single plain woven fabric was produced with a loom to attain a weavingdensity of 70 warps+70 wefts/inch (2.54 cm) using PPS fibers having 220dtex, a tensile elastic modulus of 40 cN/dtex and an elongation of 30%as warps and PTFE fibers having 440 dtex as wefts. Thereafter, the samerefining and setting as in Example 1 were performed.

The amount of compression of this woven fabric, the interval of thefluororesin fibers located on both sides of the other fiber, thethickness, the result evaluated with a friction wear testing machine,and the result of the evaluation of play as a bearing sliding materialare summarized in Table 2.

Comparative Example 2

A single plain woven fabric was produced with a loom to attain a weavingdensity of 18 warps+18 wefts/inch (2.54 cm) using carbon fibers having1000 dtex, a tensile elastic modulus of 1300 cN/dtex and an elongationof 1% and PTFE fibers having 1760 dtex as warps and wefts whilealternately arranging them at 1 (fiber): 1 (fiber). Thereafter, the samerefining and setting as in Example 1 were performed.

The amount of compression of this woven fabric, the interval of thefluororesin fibers located on both sides of the other fiber, thethickness, the result evaluated with a friction wear testing machine,and the result of the evaluation of play as a bearing sliding materialare summarized in Table 2.

Comparative Example 3

As a sliding layer, glass fibers having 300 dtex, a tensile elasticmodulus of 300 cN/dtex and an elongation of 3.5%, nylon fibers having100 dtex, a tensile elastic modulus of 40 cN/dtex and an elongation of40%, and PFFE fibers having 220 dtex were alternately arranged at 15(fibers): 35 (fibers): 15 (fibers) and used as warps, and nylon fibershaving 100 dtex, a tensile elastic modulus of 40 cN/dtex and anelongation of 40% were used as wefts. As a base layer, nylon fibershaving 100 dtex, a tensile elastic modulus of 40 cN/dtex and anelongation of 40% were used as warps and wefts. Then, a woven fabrichaving the same structure as in Example 2 was prepared, and the samerefining and setting were performed. Thereafter, impregnation with afluororesin was performed by a roll coating processing system.

The amount of compression of this woven fabric, the interval of thefluororesin fibers located on both sides of the other fiber, thethickness, the result evaluated with a friction wear testing machine,and the result of the evaluation of play as a bearing sliding materialare summarized in Table 2.

Comparative Example 4

A knitted fabric having the same structure as in Example 3 was producedusing PTFE fibers having 440 dtex as front warps and using PET fibershaving 560 dtex, a tensile elastic modulus of 120 cN/dtex and anelongation of 40% as rear warps, followed by the same refining andsetting. The amount of compression of this knitted fabric, the intervalof the fluororesin fibers located on both sides of the other fiber, thethickness, the result evaluated with a friction wear testing machine,and the result of the evaluation of play as a bearing sliding materialare summarized in Table 2.

TABLE 1 Item Example 1 Example 2 Example 3 Example 4 Used yarn ofsliding Warp PPS fiber Glass fiber Nylon fiber Carbon fiber surfaceFluorine fiber Nylon fiber Fluorine fiber Fluorine fiber Fluorine fiberPET fiber Weft PPS fiber Nylon fiber — Carbon fiber Fluorine fiberFluorine fiber Alternating ratio of Warp 1:1 1:3:3 1:1:3:2:1:4 4:4 usedyarns on sliding Weft 1:1 — — 4:4 surface Fabric structure Single plainwoven Two-layered woven Two-layered knitted Single plain woven fabricfabric fabric fabric Amount of compression (μm) 8 18 25 10 Interval (μm)between PTFE fibers 140 500 1100 4000 located on both sides Thickness(mm) 0.25 0.4 0.9 0.3 Wear resistance ⊙ ⊙ ◯ ◯ (Friction Wear Test) Play⊙ ⊙ ◯ ◯ (Bearing Sliding Material)

TABLE 2 Comparative Comparative Comparative Comparative Item Example 1Example 2 Example 3 Example 4 Used yarn of sliding Warp PPS fiber Carbonfiber Glass fiber Fluorine fiber surface Fluorine fiber Nylon fiber PETfiber Fluorine fiber Weft Fluorine fiber Carbon fiber Nylon fiber —Fluorine fiber Alternating ratio of used Warp — 1:1 15:35:15 — yarns onsliding surface Weft — 1:1 — — Fabric structure Single plain wovenSingle plain woven Two-layered woven Two-layered knitted fabric fabricfabric fabric Amount of compression (μm) 8 35 30 26 Interval (μm)between PTFE fibers — 560 5520 — located on both sides Thickness (mm)0.25 1.5 0.4 0.9 Wear resistance X Δ X X (Friction Wear Test) Play X Δ XX (Bearing Sliding Material)

INDUSTRIAL APPLICABILITY

The sliding fabric can be used particularly suitably for OA instruments,bearing members or the like because it exhibits a small amount ofcompression in the thickness direction under load application, does notcause generation of play between members, and is superior in slidingproperties and durability.

1.-12. (canceled)
 13. A sliding fabric comprising fluororesin fibers (X)and other fibers (Y) alternately arranged as warps and/or wefts on atleast one side of the fabric and an amount of compression of the fabricis 25 μm or less.
 14. The sliding fabric according to claim 13, whereinan interval between fluororesin fibers (X) positioned on both sides ofthe other fiber (Y) is 20 to 3500 μm.
 15. The sliding fabric accordingto claim 13, wherein the other fibers (Y) are of a single type.
 16. Thesliding fabric according to claim 15, wherein an equal number of thefluororesin fibers (X) and the other fibers (Y) are alternatelyarranged.
 17. The sliding fabric according to claim 15 wherein 1 to 4fibers of the fluororesin fibers (X) and 1 to 4 fibers of the otherfibers (Y) are alternately arranged.
 18. The sliding fabric according toclaim 13, wherein the fineness of the other fibers (Y) is 50 to 800dtex.
 19. The sliding fabric according to claim 13, wherein the tensileelastic modulus of the other fibers (Y) is 20 to 800 cN/dtex.
 20. Thesliding fabric according to claim 13, wherein the elongation of theother fibers (Y) is 3% or more.
 21. The sliding fabric according toclaim 13, wherein the sliding fabric is a woven fabric.
 22. The slidingfabric according to claim 21, wherein the sliding fabric is a wovenfabric composed of one layer or two layers.
 23. The sliding fabricaccording to claim 21, wherein the sliding fabric is a plain-wovenfabric.
 24. The sliding fabric according to claim 13, wherein thesliding fabric has a thickness of 1 mm or less.
 25. The sliding fabricaccording to claim 16, wherein 1 to 4 fibers of the fluororesin fibers(X) and 1 to 4 fibers of the other fiber (Y) are alternately arranged.26. The sliding fabric according to claim 22, wherein the sliding fabricis a plain-woven fabric.
 27. The sliding fabric according to claim 14,wherein the sliding fabric is a woven fabric.
 28. The sliding fabricaccording to claim 15, wherein the sliding fabric is a woven fabric. 29.The sliding fabric according to claim 16, wherein the sliding fabric isa woven fabric.
 30. The sliding fabric according to claim 17, whereinthe sliding fabric is a woven fabric.
 31. The sliding fabric accordingto claim 18, wherein the sliding fabric is a woven fabric.
 32. Thesliding fabric according to claim 19, wherein the sliding fabric is awoven fabric.